US House of Representatives Speaker Paul Ryan has been one of those who seem to shudder every time Donald Trump utters a new twittered bon mot. After Trump's latest controversial tweet, Ryan said the candidate needs to "clean up" his social media act.

"Look, anti-Semitic images, they've got no place in a presidential campaign," Ryan told WTMJ's Charlie Sykes on his radio show Tuesday. "Candidates should know that. The tweet's been deleted. I don't know what flunky put this up there. They've obviously got to fix that."

Ryan was reacting to a tweet on Trump's feed last Saturday that included an image of Hillary Clinton, a pile of cash and the words "Most Corrupt Candidate Ever!" on what looked to many like a Star of David. Was this an allusion to Wall Street being run by Jewish people, as some believe?

Trump insisted -- on Twitter, naturally -- that it was a Sheriff's star or a plain star. In which case, why change it?

Ryan is only too aware of the dangers that lurk in the tweet's connotations.

"I really believe he's got to clean up the way his new media works," he said. "But most importantly, as you know, one of the few times I spoke out against him during the primary very forcefully was in this area, when he failed to disavow supremacists, white supremacists."

The Trump campaign didn't immediately respond to a request for comment.

Ryan said it was his understanding that a member of Trump's staff was responsible for the latest Twitter snafu.

Indeed, the Trump campaign's social media director Dan Scavino on Monday issued a joint Facebook statement with the candidate that explained the image "was lifted from an anti-Hillary Twitter user where countless images appear. The sheriff's badge -- which is available under Microsoft's 'shapes' -- fit with the theme of corrupt Hillary and that is why I selected it."